CVE-2026-12022: Chrome Sandbox Escape Race Condition on macOS

Technical summary

CVE-2026-12022 is a race condition (CWE-362) in the Safe Browsing implementation of Chromium on macOS. The vulnerability exists in the interaction between the renderer process and Safe Browsing checks when processing malicious files. An attacker with existing renderer-process compromise can trigger a race condition that permits sandbox escape, potentially achieving arbitrary code execution with macOS user privileges. The high CVSS score (8.3) reflects the severity of the sandbox escape condition, though exploitation requires a prior renderer compromise.

Business impact

If exploited, this vulnerability could allow an attacker to escalate from browser compromise to full system compromise on macOS. An attacker who has already achieved code execution within Chrome (through a separate vulnerability or social engineering) could use this flaw to break the browser sandbox and gain unrestricted access to the user's system, potentially compromising sensitive data, installing malware, or establishing persistence. Organizations with macOS users running older Chrome versions face elevated risk of multi-stage attacks.

Affected systems

Google Chrome on macOS versions prior to 149.0.7827.115 are vulnerable. The vulnerability is specific to macOS; Chrome on other operating systems is not affected by this particular flaw. Users running Chrome 149.0.7827.115 or later on Mac are protected. macOS versions themselves are not directly vulnerable, but the Chrome browser running on them is the attack surface.

Exploitability

Exploitation requires a two-stage attack: first, an attacker must compromise the Chrome renderer process through a separate vulnerability or attack vector (such as a malicious website or drive-by download). Only after achieving that initial code execution can the race condition be triggered via a malicious file. The AC:H (Attack Complexity: High) in the CVSS vector indicates that successful exploitation of the race condition itself is non-trivial due to timing dependencies. The UI:R (User Interaction: Required) factor suggests user interaction is needed, likely in handling or processing a file. This significantly limits opportunistic exploitation compared to a simple remote code execution bug.

Remediation

Update Google Chrome to version 149.0.7827.115 or later on all macOS systems. Google has addressed the race condition in this version. Users should enable automatic Chrome updates to receive patches immediately upon release. Organizations should verify that Chrome's auto-update feature is not disabled by policies and ensure timely rollout of the patched version across their macOS fleet.

Patch guidance

Apply Chrome version 149.0.7827.115 or newer immediately on macOS systems. Google Chrome typically auto-updates; confirm this setting is enabled in Chrome Settings > About Google Chrome. For enterprise deployments, verify through your MDM solution that the patch version is deployed. No manual workarounds are available; patching is the only mitigation. Test the update in a non-critical environment if your organization has custom integrations with Chrome.

Detection guidance

Monitor Chrome version numbers across your macOS fleet; versions prior to 149.0.7827.115 are at risk. Endpoint detection and response (EDR) tools should flag unusual file-handling activity in Chrome processes or unexpected privilege escalations following Chrome sandbox boundaries. Log analysis should look for patterns consistent with multi-stage attacks: initial compromise of a renderer process followed by suspicious system calls or child process creation outside the sandbox. Network monitoring may detect delivery of malicious files intended to trigger the race condition, though this is likely to appear as normal file transfers without additional context.

Why prioritize this

Prioritize this vulnerability for patching because sandbox escape vulnerabilities are particularly dangerous—they transform limited browser compromise into full system compromise. Although exploitation requires prior renderer compromise, the chaining of vulnerabilities in real-world attack scenarios is common. macOS users are a frequent target for sophisticated threat actors. However, the requirement for initial renderer compromise and the high attack complexity mean this is lower priority than unrestricted remote code execution flaws, warranting prompt but not emergency response.

Risk score, explained

The CVSS 3.1 score of 8.3 (HIGH) reflects the severity of sandbox escape as an impact, combined with network attack vector and high confidentiality, integrity, and availability impact. The score is tempered by AC:H (high attack complexity due to race condition timing), PR:N (no privileges required but only after renderer compromise), and UI:R (user interaction required for file handling). The score appropriately captures that while the ultimate impact is severe, the attack path is restricted by prerequisite compromise and exploitation complexity.

Frequently asked questions